Abstract:

This study aims to use metagenomic sequencing analysis technology to quickly diagnose the possible pathogens causing the death of an Asian elephant, and then combine with conventional diagnostic techniques to analyze and confirm the etiological cause of elephant diseases, so as to provide reference for rapid diagnosis and prevention of elephant-related diseases. Autopsies were performed on dead elephant, and organs such as the heart, liver, spleen, lungs, kidneys, lymph nodes, muscles, stomach, duodenum, jejunum, colon, cecum, and pancreas were collected and sectioned for HE staining and pathological analysis; Metagenomic sequencing analysis was performed on the inguinal lymph nodes; species-specific PCR were used to amplify and sequence the characteristic genes, and an evolutionary tree was drawn to analyze its phylogenetic relationship with other strains. Data showed that necropsy and case biopsy results of dead elephant are consistent with the clinical characteristics of endothelial herpesvirus infection in elephants. Metagenomic analysis detected a large number of elephant betaherpesvirus type 1 (i.e., parent endothelial herpes virus) in the inguinal lymph nodes of elephants. The death of the elephant was probably caused by endothelial herpesvirus infection. Metagenomic technology offers valuable application prospects for the rapid diagnosis of endothelial herpesvirus infection in elephants as well as other endangered animal clinical infectious cases.

Key words: Asian elephant, endothelial herpesvirus, metagenomic analysis